Deciphering the Same Lifetimes of mRNA and the p53 Target Protein

Abstract

The tumour suppressor protein p53 is a transcription factor. After DNA damage, p53 concentrations exhibit pulsed or sustained dynamics that results in a number of target genes expression, triggering different cell fate. For p53 target genes, the mRNA decay rate constants of PUMA, MDM2, p21, and BAX are 73 h-1，0.27 h-1, 0.265 h-1, and 0.018 h-1, respectively; the protein degradation rate constants are 0.056h-1, 0.792 h-1, 0.255 h-1, and 0.0262 h-1, respectively. What is the biological significance of the same lifetimes of mRNA and protein? For sustained p53 dynamics input, using a minimal model, I found that the same lifetimes of mRNA and protein can provide high sensitive target protein expression, drive protein expression to reach maximum at the shortest time. This result may be help for designing gene expression.